Thu. Mar 28th, 2024

Given head which is a reference node to a singly-linked list. The value of each node in the linked list is either 0 or 1. The linked list holds the binary representation of a number.

Return the decimal value of the number in the linked list.

Example 1:

Input: head = [1,0,1]
Output: 5
Explanation: (101) in base 2 = (5) in base 10
/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) { val = x; }
 * }
 */
class Solution {
    public int getDecimalValue(ListNode head) {
        String num = "";
        ListNode temp = head;
        while(temp != null){
            num = num+temp.val;
            temp = temp.next;
        }
        //System.out.println(num);
        int decimalValue = Integer.parseInt(num, 2);
        return decimalValue;
    }
}